Functional Plant Biology Functional Plant Biology Society
Plant function and evolutionary biology

Plant isotopic composition provides insight into mechanisms underlying growth stimulation by AM fungi in a semiarid environment

José I. Querejeta A B C , Michael F. Allen B , María M. Alguacil A and Antonio Roldán A

A Departamento de Conservación de Suelos y Aguas, Centro de Edafología y Biología Aplicada del Segura-Consejo Superior de Investigaciones Científicas (CEBAS-CSIC), PO Box 4195, Campus Universitario de Espinardo 30 100 Murcia, Spain.

B Center for Conservation Biology, The University of California, Riverside, CA 92 521, USA.

C Corresponding author. Email:

Functional Plant Biology 34(8) 683-691
Submitted: 9 March 2007  Accepted: 16 May 2007   Published: 23 July 2007


We hypothesised that improved plant water status and enhanced transpiration are key mechanisms involved in plant growth stimulation by native arbuscular mycorrhizal fungi (AMF) in semiarid calcareous soils. Seedlings of the dryland shrubs Pistacia lentiscus L. and Retama sphaerocarpa L. were pre-inoculated with a mixture of eight native Glomus spp. fungi, or left un-inoculated, before transplanting into a degraded site in south-eastern Spain. Pre-inoculated Pistacia and Retama shrubs grew faster after transplanting, despite spontaneous colonisation of control plants by local AMF. Pre-inoculation enhanced shoot water content and shoot δ15N in both shrub species. Increased potassium uptake and improved water relations were key mechanisms behind growth stimulation by native AMF in Pistacia. Shoot δ18O (a proxy measure of stomatal conductance) was significantly less negative in AMF-inoculated than in control Pistacia seedlings, indicating enhanced cumulative transpiration in the former. In contrast, shoot δ18O was unaffected by AMF inoculation in Retama, a leafless leguminous shrub with photosynthetic stems. Growth stimulation by native AMF in Retama was attributed to increased phosphorus uptake, enhanced atmospheric nitrogen fixation and a largely nutrient-mediated improvement of plant water status. Shoot δ13C was not significantly influenced by AMF inoculation in either shrub species, thus suggesting roughly parallel upshifts in photosynthetic and transpiration rates which did not affect plant water use efficiency.

Additional keywords: Pistacia lentiscus, Retama sphaerocarpa, δ13C, δ15N, δ18O.


Allen EB Allen MF 1980 Natural re-establishment of vesicular-arbuscular mycorrhizae following stripmine reclamation in Wyoming. Journal of Applied Ecology 17 139 147 doi:10.2307/2402969

Allen MF (1991) ‘The ecology of mycorrhizae.’ (Cambridge University Press: Cambridge)

Allen MF Boosalis MG 1983 Effects of 2 species of VA-mycorrhizal fungi on drought tolerances of winter wheat. New Phytologist 93 67 76 doi:10.1111/j.1469-8137.1983.tb02693.x

Allen MF Smith WK Moore TS Christensen M 1981 Comparative water relations and photosynthesis of mycorrhizal and non-mycorrhizal Bouteola gracilis HBK Lag ex Steud. New Phytologist 88 683 693

Allen MF Swenson W Querejeta JI Egerton-Warburton LM Treseder KK 2003 Ecology of mycorrhizae: a conceptual framework for complex interactions among plants and fungi. Annual Review of Phytopathology 41 271 303

Augé RM 2001 Water relations, drought and vesicular-arbuscular mycorrhizal symbiosis. Mycorrhiza 11 3 42 doi:10.1007/s005720100097

Azcón R Barea JM 1997 Mycorrhizal dependency of a representative plant species in Mediterranean shrublands (Lavandula spica L.) as a key factor to its use for revegetation strategies in desertification-threatened areas. Applied Soil Ecology 7 83 92 doi:10.1016/S0929-1393(97)00013-9

Azcón-Aguilar C Palenzuela J Roldán A Bautista R Vallejo R Barea JM 2003 Analysis of the mycorrhizal potential in the rhizosphere of representative plant species from desertification-threatened Mediterranean shrublands. Applied Soil Ecology 22 29 37 doi:10.1016/S0929-1393(02)00107-5

Barbour MM 2007 Stable oxygen isotope composition of plant tissue: a review. Functional Plant Biology 34 83 94 doi:10.1071/FP06228

Barbour MM Farquhar GD 2000 Relative humidity and ABA-induced variation in carbon and oxygen isotope ratios of cotton leaves. Plant, Cell & Environment 23 473 485 doi:10.1046/j.1365-3040.2000.00575.x

Bednarz CW Oosterhuis DM Evans RD 1998 Leaf photosynthesis and carbon isotope discrimination of cotton in response to potassium deficiency. Environmental and Experimental Botany 39 131 139 doi:10.1016/S0098-8472(97)00039-7

Caravaca F Figueroa D Alguacil MM Roldán A 2003 Application of composted urban residue enhanced the performance of afforested shrub species in a degraded semiarid land. Bioresource Technology 90 65 70 doi:10.1016/S0960-8524(03)00087-7

Carpenter AT Allen MF 1988 Responses of Hedysarum boreale Nutt to mycorrhizas and Rhizobium- Plant and soil nutrient changes in a disturbed shrub steppe. New Phytologist 109 125 132 doi:10.1111/j.1469-8137.1988.tb00227.x

Cernusak LA Arthur DJ Pate JS Farquhar GD 2003 Water relations link carbon and oxygen isotope discrimination to phloem sap sugar concentration in Eucalyptus globulus. Plant Physiology 131 1544 1554 doi:10.1104/pp.102.016303

Cernusak LA Pate JS Farquhar GD 2004 Oxygen and carbon isotope composition of parasitic plants and their hosts in southwestern Australia. Oecologia 139 199 213 doi:10.1007/s00442-004-1506-6

Clark RB Zeto SK 2000 Mineral acquisition by arbuscular mycorrhizal plants. Journal of Plant Nutrition 23 867 902

Cooper RB Blaser RE Brown RH 1967 Potassium nutrition effects on net photosynthesis and morphology of alfalfa. Soil Science 31 231 235

De Niro MJ Epstein S 1979 Relationship between the oxygen isotope ratios of terrestrial plant cellulose, carbon dioxide, and water. Science 204 51 53

Domingo F Gutiérrez L Brenner AJ Aguilera C 2002 Limitation to carbon assimilation of two perennial shrub species in semi-arid south-east Spain. Biologia Plantarum 45 213 220 doi:10.1023/A:1015136421445

Ehleringer JR Philips SL Comstock JP 1992 Seasonal variation in the carbon isotopic composition of desert plants. Functional Ecology 6 396 404 doi:10.2307/2389277

Evans RD 2001 Physiological mechanisms influencing plant nitrogen isotope composition. Trends in Plant Science 6 121 126 doi:10.1016/S1360-1385(01)01889-1

Farquhar GD Ehleringer JR Hubick KT 1989 Carbon isotope discrimination and photosynthesis. Annual Review of Plant Physiology and Plant Molecular Biology 40 503 537 doi:10.1146/annurev.pp.40.060189.002443

Ferrol N Calvente R Cano C Barea JM Azcón-Aguilar C 2004 Analysing arbuscular mycorrhizal fungal diversity in shrub-associated resource islands from a desertification-threatened semiarid Mediterranean ecosystem. Applied Soil Ecology 25 123 133 doi:10.1016/j.apsoil.2003.08.006

Giovannetti M Mosse B 1980 An evaluation of techniques for measuring vesicular-arbuscular mycorrhizal infection in roots. New Phytologist 84 489 499 doi:10.1111/j.1469-8137.1980.tb04556.x

Haase P Pugnaire FI Fernandez EM Puigdefabregas J Clark SC Incoll LD 1996 An investigation of rooting depth of the semiarid shrub Retama sphaerocarpa (L.) Boiss. by labelling of ground water with a chemical tracer. Journal of Hydrology 177 23 31 doi:10.1016/0022-1694(95)02794-7

Haase P Pugnaire FI Clark SC Incoll LD 2000 Dynamics of the cohorts of cladodes and related effects on reproduction in the shrub Retama sphaerocarpa in semi-arid south-eastern Spain. Plant Ecology 146 105 115 doi:10.1023/A:1009817100422

Handley LL Azcón R Ruiz-Lozano JM Scrimgeour CM 1999 Plant δ15N associated with arbuscular mycorrhization, drought and nitrogen deficiency. Rapid Communications in Mass Spectrometry 13 1320 1324 doi:10.1002/(SICI)1097-0231(19990715)13:13<1320::AID-RCM607>3.0.CO;2-M

Helgason T Merryweather JW Denison J Wilson P Young JPW Fitter AH 2002 Selectivity and functional diversity in arbuscular mycorrhizas of co-occurring fungi and plants from a temperate deciduous woodland. Journal of Ecology 90 371 384 doi:10.1046/j.1365-2745.2001.00674.x

Hoffmann WA Poorter H 2002 Avoiding bias in calculations of relative growth rate. Annals of Botany 90 37 42 doi:10.1093/aob/mcf140

Humble GD Raschke K 1971 Stomatal opening quantitatively related to potassium transport. Plant Physiology 48 447 453

Husband R Herre EA Turner SL Gallery R Young JPW 2002 Molecular diversity of arbuscular mycorrhizal fungi and patterns of host association over time and space in a tropical forest. Molecular Ecology 11 2669 2678

Jaggi M Saurer M Fuhrer J Siegwolf R 2003 Seasonality of δ18O in needles and wood of Picea abies. New Phytologist 158 51 59 doi:10.1046/j.1469-8137.2003.00711.x

Jonasson S Medrano H Flexas J 1997 Variation in leaf longevity of Pistacia lentiscus and its relationship to sex and drought stress inferred from leaf δ13C. Functional Ecology 11 282 289 doi:10.1046/j.1365-2435.1997.00090.x

Jordan-Meille L Pellerin S 2004 Leaf area establishment of a maize (Zea mays L.) field crop under potassium deficiency. Plant and Soil 265 75 92 doi:10.1007/s11104-005-0695-z

Kaya C Higgs D Kirnak H Tas I 2003 Mycorrhizal colonisation improves fruit yield and water use efficiency in watermelon (Citrullus lanatus Thunb.) grown under well-watered and water-stressed conditions. Plant and Soil 253 287 292 doi:10.1023/A:1024843419670

Klironomos JN 2003 Variation in plant response to native and exotic arbuscular mycorrhizal fungi. Ecology 84 2292 2301

Koide RT 2000 Functional complementarity in the arbuscular mycorrhizal symbiosis. New Phytologist 147 233 235

Marulanda A Azcón R Ruiz-Lozano JM 2003 Contribution of six arbuscular mycorrhizal fungal isolates to water uptake by Lactuca sativa plants under drought stress. Physiologia Plantarum 119 526 533 doi:10.1046/j.1399-3054.2003.00196.x

Milla R Palacio-Blasco S Maestro-Martínez M Montserrat-Marti G 2006 Phosphorus accretion in old leaves of a Mediterranean shrub growing at a phosphorus-rich site. Plant and Soil 280 369 372 doi:10.1007/s11104-005-3529-0

Miller RM Miller SP Jastrow JD Rivetta CB 2002 Mycorrhizal mediated feedbacks influence net carbon gain and nutrient uptake in Adropogon gerardii. New Phytologist 155 149 162 doi:10.1046/j.1469-8137.2002.00429.x

Querejeta JI Barea JM Allen MF Caravaca F Roldán A 2003 Differential response of δ13C and water use efficiency to arbuscular mycorrhizal infection in two aridland woody plant species. Oecologia 135 510 515

Querejeta JI Allen MF Caravaca F Roldán A 2006 Differential modulation of host plant δ13C and δ18O by native and non-native arbuscular mycorrhizal fungi in a semiarid environment. New Phytologist 169 379 387

Requena N Pérez-Solís E Azcón-Aguilar C Jeffries P Barea JM 2001 Management of indigenous plant–microbe symbioses aids restoration of desertified ecosystems. Applied and Environmental Microbiology 67 495 498 doi:10.1128/AEM.67.2.495-498.2001

Ruiz-Lozano JM Azcón R 1995 Hyphal contribution to water uptake in mycorrhizal plants as affected by the fungal species and water status. Physiologia Plantarum 95 472 478 doi:10.1111/j.1399-3054.1995.tb00865.x

Ruiz-Lozano JM Azcón R Gómez M 1995 Effects of arbuscular-mycorrhizal Glomus species on drought tolerance: physiological and nutritional plant responses. Applied and Environmental Microbiology 61 456 460

Scheidegger Y Saurer M Bahn M Siegwolf R 2000 Linking stable oxygen and carbon isotopes with stomatal conductance and photosynthetic capacity: a conceptual model. Oecologia 125 350 357

Shearer G Kohl DH Virginia RA Bryan BA Skeeters JL Nielsen ET Sharifi MR Rundel PW 1983 Estimates of N2 fixation from variation in the natural abundance of N15 in Sonoran desert ecosystems. Oecologia 56 365 373 doi:10.1007/BF00379714

Sheshshayee MS Bindumadhava H Ramesh R Prasad TG Lakshminarayana MR Udayakumar M 2005 Oxygen isotope enrichment (Δ18O) as a measure of time-averaged transpiration rate. Journal of Experimental Botany 56 3033 3039 doi:10.1093/jxb/eri300

Stahl PD Smith WK 1984 Effects of different geographic isolates of Glomus on the water relations of Agropyron smithii. Mycologia 76 261 267 doi:10.2307/3793102

Tobar R Azcón R Barea JM 1994 Improved nitrogen uptake and transport from N15-labeled nitrate by external hyphae of arbuscular mycorrhiza under water stress conditions. New Phytologist 126 119 122 doi:10.1111/j.1469-8137.1994.tb07536.x

Tsialtas JT Handley LL Kassioumi MT Veresoglou DS Gagianas AA 2001 Interspecific variation in potential water use efficiency and its relation to plant species abundance in a water limited grassland. Functional Ecology 15 605 614 doi:10.1046/j.0269-8463.2001.00555.x

Van der Heijden MGA Klironomos JN Ursic M Moutoglis P Streitwolf-Engel R Boller T Wiemken A Sanders IR 1998 Mycorrhizal fungal diversity determines plant diversity, ecosystem variability and productivity. Nature 396 69 72 doi:10.1038/23932

Van der Heijden MGA Klironomos JN Ursic M Moutoglis P Streitwolf-Engel R Boller T Wiemken A Sanders IR 1999 ‘Sampling effect’, a problem in biodiversity manipulation? A reply to David A. Wardle. Oikos 87 408 410 doi:10.2307/3546758

Van der Heijden MGA Streitwolf-Engel R Riedl R Siegrist S Neudecker A Ineichen K Boller T Wiemken A Sanders I 2006 The mycorrhizal contribution to plant productivity, plant nutrition and soil structure in experimental grassland. New Phytologist 172 739 752 doi:10.1111/j.1469-8137.2006.01862.x

Wang XF Yakir D Avishai M 1998 Non-climatic variations in the oxygen isotopic compositions of plants. Global Change Biology 4 835 849 doi:10.1046/j.1365-2486.1998.00197.x

Wheeler CT Tilak M Scrimgeour CM Hooker JE Handley LL 2000 Effects of symbiosis with Frankia and arbuscular mycorrhizal fungus on the natural abundance of 15N in four species of Casuarina. Journal of Experimental Botany 51 287 297 doi:10.1093/jexbot/51.343.287

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